The Synthetic Routes of 6-chloro-4-methyl-2H-pyridazin-3-one

The 6-chloro-4-methyl-2H-pyridazin-3-one is an important pharmaceutical intermediate and is used in the synthesis of various drugs.
It has been widely studied in the chemical industry and several synthetic routes have been reported for its preparation.
In this article, we will discuss some of the most commonly used synthetic routes for the preparation of 6-chloro-4-methyl-2H-pyridazin-3-one.

1. Electrophilic substitution reaction

One of the most common methods for the synthesis of 6-chloro-4-methyl-2H-pyridazin-3-one is through electrophilic substitution reaction.
In this method, a suitable electrophile is reacted with pyridazine-2,6-dicarboxylic acid, which is then hydrolyzed to give 6-chloro-4-methyl-2H-pyridazin-3-one.
This method is simple and efficient and offers good yields.

2. Halogenation

Another commonly used method for the synthesis of 6-chloro-4-methyl-2H-pyridazin-3-one is halogenation.
In this method, a suitable halogen is reacted with pyridazine-2,6-dicarboxylic acid to give the desired product.
This method is also simple and efficient and offers good yields.

3. Nitration

Nitration is another method that can be used for the synthesis of 6-chloro-4-methyl-2H-pyridazin-3-one.
In this method, pyridazine-2,6-dicarboxylic acid is treated with a suitable nitrating agent, such as nitric acid or sodium nitrite, to give the desired product.
This method is also efficient and offers good yields.

4. Reductive nitration

Reductive nitration is another method that can be used for the synthesis of 6-chloro-4-methyl-2H-pyridazin-3-one.
In this method, pyridazine-2,6-dicarboxylic acid is treated with a suitable nitrating agent, such as nitric acid or sodium nitrite, in the presence of a reducing agent, such as hydroxylamine or ascorbic acid.
This method is efficient and offers good yields.

5. Hydrolysis

Hydrolysis is another method that can be used for the synthesis of 6-chloro-4-methyl-2H-pyridazin-3-one.
In this method, pyridazine-2,6-dicarboxylic acid is treated with water to give the desired product.
This method is simple and efficient but can be time-consuming.

6. Reductive hydrolysis

Reductive hydrolysis is another method that can be used for the synthesis of 6-chloro-4-methyl-2H-pyridazin-3-one.
In this method, pyridazine-2,6-dicarboxylic acid is treated with water in the presence of a reducing agent, such as hydroxylamine or ascorbic acid, to give the desired product.
This method is efficient and offers good yields.

In conclusion, there are several synthetic routes for the preparation of 6-chloro-4-methyl-2H-pyridazin-3-one, and the most suitable method depends on various factors, such as the availability of starting materials, reaction conditions, and desired yield.
The methods discussed above are the most commonly used methods in the chemical industry and offer good yields.
As the demand for pharmaceuticals continues to grow, the synthesis of 6-chloro-4-methyl-2H-pyridazin-3-one will remain an important area of research and development in the chemical industry.